13551
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 18072
- Proper Divisor Sum (Aliquot Sum)
- 4521
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 9032
- Möbius Function
- 1
- Radical
- 13551
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- no
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- no
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 244
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- Squarefree Number
- yes
- Prime Power
- no
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- a(n) gives smallest number requiring n iterations of the map i -> A053392(i) to reach zero.at n=26A060630
- Lucky numbers for which both the sum of the digits and the product of the digits is also a lucky number.at n=31A118559
- a(n) = 484*n - 1.at n=27A158330
- a(n) = 28*n^2 - 1.at n=21A158554
- Number of symmetry classes of 3 X 3 semimagic squares with distinct positive values and magic sum n.at n=47A173725
- Number of 0..n arrays of length 6 with each element differing from at least one neighbor by 1 or less, starting with 0.at n=25A221685
- Number of (n+1)X(1+1) 0..1 arrays x(i,j) with row sums sum{j^2*x(i,j), j=1..1+1} nondecreasing, and column sums sum{i^2*x(i,j), i=1..n+1} nondecreasing.at n=45A232871
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 374", based on the 5-celled von Neumann neighborhood.at n=31A271459
- a(n) = Sum_{k=1..n} k * tau_3(k), where tau_3 is A007425.at n=45A318750
- a(n) is the least exponent k greater than 1 such that prime(n)^k starts and ends in prime(n).at n=42A320775
- a(n) is the number of distinct pairs that can be made in exactly n iterations of either of the two maps (x, y) -> (x OR (2^y), 0) or (x, y) -> (x, y+1), starting from (0,0).at n=32A353150